News: More Links Between Gut Health & Autism as 'Probiotic' Transplant Trials Show Some Success

Autism affects 1 in 68 children in the US, and that means it affects at least 1 in every 68 families. More boys than girls are diagnosed as being on the autism spectrum, and it's estimated that almost 60,000 12-year-olds in the US have autism. That is a 37-fold increase from the 1 in 2,500 children diagnosed just 30 years ago.

As more kids are diagnosed, the heat is on for the search for a cause and cure. Results from a new clinical trial of "probiotic" bacterial transplants not only links the condition to the gut, but could offer some symptom relief to those who have it.

Autism Spectrum Disorder

Usually children with autism are diagnosed before they are three years old. The disorder lasts a lifetime, but sometimes symptoms improve with time and treatment. Yet it's tough to nail exactly what autism is.

Autism is the core of autism spectrum disorder (ASD), meaning there is a broad range of conditions that fall under the diagnosis. Autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), and Asperger syndrome all fall under the diagnosis of ASD. In real life, this means that a child diagnosed with ASD can have a spectrum of symptoms that may be as subtle as behavioral differences to as severe as being unable to speak, understand, or interact with others.

People with ASD may show unusual interests or behaviors, such as lining up objects, obsessive interests, strictly following routines and need for order, or body rocking, spinning, hand flapping, and other repetitive motions.

Currently, there is no drug approved by the Food and Drug Administration (FDA) to reduce ASD symptoms. Children with autism are usually treated with behavioral therapy or medications aimed at reducing sleep disturbance, seizures, and gastrointestinal distress that many experience. Addressing these conditions can improve attention, learning, and related behaviors.

The new research from Arizona State University, the University of Arizona, Northern Arizona University, Ohio State University, and the University of Minnesota, to be published in microbiomejournal.biomedcentral.com/Microbiome, presents a novel treatment for autism involving, of all things, bacteria found in feces.

The idea of a cure for autism is controversial; many disability-rights advocates point out its connection to prejudice and violence against autistic and other disabled people. Many autistic people see autism as part of who they are, not as something wrong with them that could be 'cured'. Additionally, the behavioral changes in this study could be caused by the gastrointestinal problems themselves abating, and kids usually being calmer and happier when they're physically feeling better.

What Does Gut Bacteria Have to Do with Autism?

Children with ASD have significantly more gastrointestinal problems than those without ASD. They have over 3.5 higher rates of diarrhea, and constipation, and about 2.5 times higher rates of abdominal pain.

These observations have prompted researchers to investigate the role of gut bacteria in autism. Several studies have already shown that gut bacteria—the intestinal microbiome—is different in children with a diagnosis of ASD. The presence of autistic symptoms has been associated with lower amounts of the bacteria Prevotella, Coprococcus, and Veillonellaceae, in the gut, but the significance of those findings is not yet clear.

The new study included 18 young people ages 7 to 16 with ASD. The aim of the first part of the study was to reduce the total amount of bacteria in the gut of the participants, in preparation for receiving new gut bacteria. They were given 14 days of oral vancomycin, an antibiotic that kills gut bacteria. On day 15, parents gave their children a drink called MoviPrep that flushed their bowels, removing most remaining gut bacteria and vancomycin.

The next part of the study was aimed at restoring good bacteria to the gut of the children. They were given either a mixture of bacteria in chocolate milk, milk substitute, or juice for two days, or a single rectal dose of bacteria given similar to an enema. The bacteria they were given was cultured from stool samples from healthy individuals.

These preparations dosed the children with bacteria that served as probiotics—beneficial organisms that the researchers hoped would affect their ASD symptoms. After the first oral or fecal dose, all children received the probiotic treatment as daily oral doses for eight more weeks. The kids were evaluated for eight weeks after the treatments ended to assess long-term effects.

Sixteen of the 18 children with ASD showed more than a 50% improvement of their symptoms of diarrhea, constipation, and abdominal pain, as measured by their parents on a Gastrointestinal Symptom Rating Scale. What's really interesting is that there was also a 20-25% improvement in autism behaviors, including improved social skills and better sleep habits, again assessed by parents using several different scales of measuring ASD symptoms.

"We saw a big increase in microbe diversity and a big increase in certain bacteria, especially Prevotella, which we previously found was low in children with autism spectrum disorders," co-lead author Dae-Wook Kang, from Arizona State University, said in a press release.

This was a Phase 1 trial to show safety and efficacy of the treatment. Next, will come Phase 2 and 3 trials where doses and effectiveness will be measured. Then the FDA will decide if this treatment will be approved for ASD.

Future recipients of this treatment will be happy to know that there was no significant difference in clinical outcomes between those who received the initial probiotic dose orally or rectally.

"Although we see promise in this treatment, it is important that parents and children consult their physicians," remarked one of the other study leaders, Rosa Krajmalnik-Brown. "Improper techniques can result in severe gastrointestinal infection."